Apparatus for holding intestines out of an operative field

ABSTRACT

A nonabsorbent holding member adapted for use within an abdominal cavity of a patient defined by an anterior wall, a posterior wall and two lateral walls to keep the patient&#39;s bowels out of the operative field during open pelvic surgery. The holding member has a peripheral edge formed of a resiliently deformable material sized to be received within the abdominal cavity. The resilient deformation of at least a portion of the peripheral edge of the holding member results in a residual reactive force against the abdominal cavity to assist in positioning the holding member in the abdominal cavity.

This is a, now U.S. Pat. No. 5,651,762, divisional application of Ser.No. 08/405,529 filed on Mar. 16, 1995 which is a continuation-in-part ofapplication Ser. No. 08/089,713 filed Jul. 9, 1993, now abandoned.

FIELD OF THE INVENTION

The invention relates to an apparatus for holding intestines out of anoperative field. In particular, the invention relates to a nonabsorbentbean-shaped surgical holding member sized to be received in a patient'sabdominal cavity to hold the omentum and intestines out of the operativefield during open transabdominal pelvic surgery. An operating procedurefor using the holding member is also disclosed.

BACKGROUND OF THE INVENTION

When pelvic surgery is performed trans-vaginally or with a laparoscopethere is generally no delay in return of normal motility to theintestines. However, when open pelvic surgery is required,intra-operative bowel (e.g. intestine and omentum) irritation canresult.

Peristalsis is successive waves of involuntary contractions passingalong the walls of the intestine forcing the contents onward. Theabsence or reduction of peristalsis following surgery is referred to aspost-operative ileus. Ileus results in bloating, cramping, nausea andvomiting as a result of the mechanical and functional obstruction of theintestines during post-operative recovery. This usually increases ahospital stay by twenty-four to forty-eight hours.

Additionally, during open pelvic surgery the surgeon must be carefulwhile holding the intestines out of the operative field so as not toconstrict, or worse, cut off proper flow of the patient's vena cava andaorta that provides blood to and from the heart.

The use of devices for retaining and preventing movement of the viscera,or organs, adjoining the field of an abdominal surgical procedure iscommon surgical practice. Such retaining devices include pads, such astowels or large sponges, such as a 4 ply-18"×18" disposable laparotomysponges supplied by Kendell Healthcare Products Company, the KendellCompany, of Mansfield, Mass. These loose woven cloth sponges are used topack the omentum and the intestines into the abdominal cavity and areoften held in place by a metal retractor blade of sufficient width anddepth, such as used with the Weinstein retractor device, the"BOOKWALTER" retractor system, or the O'Sullivan-O'Connor self-retainingabdominal retractor. Both the "BOOKWALTER" and O'Sullivan-O'Connorretractors are distributed by Codman and Shurtleff, Inc. of Randolph,Mass. The O'Sullivan-O'Connor retractor includes two fixed blades, tworemovable small blades and one large removable blade.

U.S. Pat. Nos. 4,533,356 and 5,346,484 propose surgical devices forinternal use during surgical abdominal operations. However, these twosurgical devices, like the pads, are designed to absorb blood and/orwound fluid. It is the inventor's present belief that a nonabsorbent, ascompared to an absorbent, holding member reduces irritation and theresultant post-operative ileus.

A disposable abdominal retracting pad known by the trade name DISARP isdisclosed in U.S. Pat. No. 4,889,107. This retractor is stated tocomprise a flexible flat metal rod having no memory enclosed in urethaneplastic foam in turn wrapped in an absorbent woven nylon.

U.S. Pat. No. 4,889,107 further discloses an abdominal retractor thatcomprises a barrier member forming a surgical dam for retaining viscerain an abdominal cavity during surgery which is stated to be nonabsorbentand is capable of being bent to a selected configuration. A core membermade from a soft, malleable aluminum or, alternatively, a metal capableof returning to a predetermined shape after being heated to a certaintemperature ("Nitinol") is enclosed within the barrier member to retainthe barrier member in a selected configuration. A flexible material suchas a plastic foam or silicone rubber encloses the core member and bothare covered by a material impermeable to the passage of blood such assilicone rubber, polyvinylchloride or latex.

While U.S. Pat. No. 4,889,107 discloses in FIG. 4 that the side wallsand end walls of the barrier member are upright when positioned adjacentto a surgical field in an abdominal cavity, there is no teaching of afixed presized indentation in the barrier member to provide proper flowthrough the patient's aorta and vena cava to and from the heart. A fixedpresized indentation would relieve the surgeon from physically having tobend the member to a proper configuration. Also, it is believed that thebarrier member of U.S. Pat. No. 4,889,107 could bend out of the desiredconfiguration either before or during its use, placing a lifethreatening constriction on the patient's aorta or vena cava. Further,an indentation in the barrier member of U.S. Pat. No. 4,899,107 was notdiscussed, disclosed or deemed necessary since the barrier member wasnot contemplated to be positioned within the walls of the abdominalcavity but, as shown in FIG. 4, the rectangular-shaped barrier member isonly placed adjacent to a surgical field with the top and end wallsfree.

A presized nonabsorbent holding member with a presized or preshapedindentation to allow proper flow of the patient's aorta and vena cavawould be desirable. Additionally, an operation procedure whereby thenonabsorbent holding member having a slippery surface that blocks thebowels is positioned between the anterior, lateral and posterior wallsof the abdominal cavity would reduce irritation of the bowels and theresultant post-operative discomfort of ileus and shorten the hospitalstay while providing a more positive means for holding the bowels out ofthe operative field during open pelvic surgery.

SUMMARY OF THE INVENTION

A nonabsorbent holding member having a slippery surface adapted for usewithin a patient's abdominal cavity defined by an anterior wall, aposterior wall and two lateral walls to keep the omentum and intestinesout of the operative field during open pelvic surgery is provided. Aholding member having a peripheral edge formed of a resilientlydeformable foam is presized to be received within the abdominal cavity.The resilient deformation of at least a portion of the peripheral edgeof the holding member results in a residual reactive force against theabdominal cavity walls. This residual reactive force assists inpositioning of the holding member in the abdominal cavity.Alternatively, the holding member can have a cross section equal orgreater than the abdominal cavity to substantially block the intestinesin the upper abdomen from the operative field. This blocking or holdingof the intestines is achieved while a presized indentation in theholding member allows proper fluid flow to and from the heart via thepatient's aorta and vena cava. The plastic foam in the holding member isadvantageously compressed adjacent a core formed of a material having amemory to increase the density of the foam adjacent the core to protectthe aorta and vena cava. The material used for the holding memberincluding the core has a memory when it has a capacity for returning toa former condition or shape independent of external forces, such as, butnot limited to, unfolding, uncoiling, unrolling, unbending by the user.

Additionally, a procedure for using the nonabsorbent holding member toassist in holding a portion of the intestines within the abdominalcavity defined by the anterior wall, posterior wall and two lateralwalls during the open pelvic operation is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

The object, advantages and features of the invention will become moreapparent by reference to the drawings which are appended hereto andwherein like letters or numerals indicate like parts and wherein anillustrative embodiment of the invention is shown, of which:

FIG. 1 is an elevational view of the positioning of a conventionalretractor on a patient positioned in the "Trendelenburg" position beforea holding member of the present invention is inserted in the abdominalcavity;

FIG. 2 is an enlarged cross section elevational view of the patient'sabdominal cavity with a holding member inserted between the anteriorwall adjacent the umbilicus and the posterior wall around a patient'svena cava and aorta;

FIG. 3 is a top view of a conventional four-way retractor positioned onthe patient as shown in FIGS. 1 and 2;

FIG. 4 is a resiliently deformable plastic foam portion of analternative embodiment of the holding member of the present invention;

FIG. 5 is a section taken along lines 5--5 of FIG. 4 additionallyillustrating the alignment of the side plates of the core beforeassembly;

FIG. 6 is a view similar to FIG. 4 with the side plates assembled and acover or coating provided over the alternative embodiment of the holdingmember of the present invention;

FIG. 7 is a section view taken along lines 7--7 of FIG. 6;

FIG. 8 is an enlarged section view taken along lines 8--8 of FIG. 6better illustrating the cover or coating for the holding member of thepresent invention;

FIG. 9 is another alternative embodiment of the present inventioncomprising an inflatable tube;

FIG. 10 is a section view taken along lines 10--10 of FIG. 9;

FIG. 11 is an enlarged section view taken along lines 11--11 of FIG. 2better illustrating the positioning of a holding member of the presentinvention between the abdominal cavity walls;

FIG. 12 is an enlarged section view taken along lines 12--12 of FIG. 9better illustrating the cover or coating for the alternative embodimentof the holding member of the present invention;

FIG. 13 is the preferred embodiment of the present invention with aportion of the holding member foam and its nonabsorbent cover or coatingcut away to better illustrate the core, the remaining portion of thecore in the holding member shown in phantom view;

FIG. 14 is a section view taken along lines 14--14 of FIG. 13; and

FIG. 15 is a bottom view of the holding member of FIG. 14.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

The preferred embodiment of the holding member, generally indicated at40 in FIGS. 13, 14 and 15, is sized to be received within the abdominalcavity C of a patient p defined by an anterior wall W₁, a posterior wallW₂, lateral wall W₃ and lateral wall W₄, as generally shown in FIGS. 2and 11. The holding member 40 is preferably constructed of a coatedplastic foam completely embedding a more rigid core, as will bedescribed below in detail In alternative embodiments, as shown in FIGS.2 and 4 to 11, holding members, generally indicated as 10 and 10', arefabricated from a coated plastic foam and a core, or a coated inflatabletube having a foam embedded core, respectively, as will be describedbelow in detail.

Turning first to FIG. 5, in one alternative embodiment the holdingmember 10 includes a resiliently deformable plastic foam member 12having an upper or front surface 60, a lower or rear surface 62, andthree bores 12A, 12B and 12C therein. Though three bores are shown inthe member 10, a different number of bores could be used. The plasticfoam member 12 is bean-shaped having an overall curved configurationincluding an indentation 14. A preferred medium sized holding member 10would include the center height from the top of the indentation 14 tothe top of the foam member 12 through the axis of bore 12B ofapproximately 10 centimeters. The overall length of the holding member10 along the bottom of bores 12A and 12C and the tangent of indentation14 is approximately 26.0 centimeters. Preferably, the bores areapproximately 2.0 centimeters in diameter. The overall height of theholding member 10 is approximately 16.0 centimeters with a total uniformthickness of approximately 2.7 centimeters. This 16.0 centimeter overallheight and 10.0 centimeter actual holding member height provides a 6.0centimeter clearance from the top of indentation 14 to the bottom of theholding member about the patient's aorta and vena cava. The width ofeach side plate 16A and 16B of the core 16 is 4.5 centimeters. Theplastic foam member 12 is preferably cut from a cellular silicone foamavailable from Rogers Corporation of Woodstock, Conn. under thetrademark "PORON" S2000 silicone though could be fabricated from othercomparable medical grade polymers or materials. Other possible materialsthat could be used for the holding member could include those disclosedin U.S. Pat. Nos. 2,938,519; 3,863,639; 4,637,377; 4,777,943; 4,899,107and 4,981,465, which are incorporated by references herein for allpurposes.

Though not shown, the holding member 10' of FIGS. 9 and 10 could have arigid core, such as two cores like core 26, relocated on opposed outsidesurfaces, such as the front surface 64 and rear surface 66 of theholding member to provide a more positive engagement surface between theretractor blade R₄ and the holding member 10'. Additionally, a positiveattachment means could be provided between the retractor blade R₄ andthe core of any of the disclosed holding members; such as a keyhole inthe core and a corresponding key member on the retractor blade R₄.

Returning to FIG. 5, the side plates 16A and 16B are preferably moldedfrom a fairly stiff elastomer, such as a liquid that is injection moldedand heat and pressure vulcanized to provide a gum-type material with amemory. Such liquid has been previously supplied as No. 7-6860 by DowCorning of Midland, Mich. or is now available as Part No. PS1771 byApplied Silicone Corporation of Ventura, Calif. The three cylindricalconnecting members 18A, 18B and 18C are preferably 1 centimeter inlength Upon assembly of side plate 16A with side plate 16B, the foammember 12, which is preferably 2.7 centimeters thick in its uncompressedstate, is compressed to 1 centimeter. This approximately 3 to 1compression of the foam will increase the density of the foam adjacentthe central core or side plates 16A and 16B to further protect thepatient's aorta A and vena cava V during insertion and use of theholding member. Any suitable adhesive for assembly of connecting members18A, 18B and 18C to side plates 16A and 16B may be used or commonmechanical locking devices for connecting the core 16 together may beused. A preferred adhesive is No. 586 NuSil Medical Grade Adhesive--1137by NuSil Silicone Technologies of Carpinteria, Calif.

After the side plates have been assembled, the entire holding member 10preferably is coated with a polymer layer or coating 20, such as adimethyl silicone elastomer, as best shown in FIG. 8. The slipperyresultant surface on the front surface 60 and the rear surface 62 ofholding member from this elastomer coating further reduces tissuereaction by allowing the bowels to contact and move relative to theholding member without significant friction. This layer 20, as discussedfurther below, must be soft, compliant, pliable, resiliently deformableand nonporous so that it permits compression of the foam member 12 whilebeing nonabsorbent. This layer 20 may be applied by dipping or sprayingonto the foam member 12. Preferably, the holding member is dipcoated bydipping in the coating material for approximately 5 minutes and allowedto air dry for approximately 1 hour then re-dipped for another 5 minutesand again allowed to air dry for approximately another 1 hour. Theholding member is then placed into an oven and cured at 300° F. forapproximately 3 hours. A preferred coating is Part No. 40,000 medicalgrade dimethyl silicone elastomer by Applied Silicone Corporation ofVentura, Calif. dispersed in Syxlene.

After the holding member 10 is completely coated, the layer 20 coveringthe front surface 60 of the holding member 10 could, if desired, beperforated with a plurality of holes 22 to allow air to vent withcompression and expansion of the holding member. The holding members, asshown in the Figures, would be wrapped, packaged and terminallysterilized by gas or gamma radiation. As can be seen, a simplemanufacture process could be used to reduce the cost of the holdingmember.

As best shown in FIGS. 9 and 10, an alternative embodiment of theholding member 10' having an upper or front surface 64 and a lower orrear surface 66, is constructed of an air filled tube 24 generallyhaving the same overall U-shaped or bean-shaped configuration anddimensions as holding member 10. Though the holding member 10' is shownconstructed of one continuous tube, the tube could comprise a pluralityof chambers (not shown) strategically placed to prevent inadvertentdeflation during an operation. The central core 26 of the member 10'preferably is fabricated from a vulcanized silicone elastomer having amemory, as described above, embedded in a foam 28, such as the "PORON"cellular silicone foam, as described above. The foam 28 is in turnattached to tube 24 by a conventional heating process or an adhesive,such as the above-described NuSil-1137 adhesive. As best shown in FIG.12, the holding member 10' is preferably dipcoated, as described above,by a soft, flexible, pliable, nonporous and nonabsorbent material 34,such as Applied Part No. 40,000 medical grade dimethyl siliconeelastomer or other suitable material similar to the preferred coating.

Turning now to FIGS. 13-15, the preferred holding member 40 having anupper or front surface 68, and a lower or rear surface 70 is shown. Thepreferred holding member includes a core 42, as best shown in FIGS. 13and 14, preferably made of a vulcanized silicone elastomer previouslyavailable from Dow Corning and now available from Applied SiliconeCorporation, as described above. This core is centrally embedded in acellular silicone foam such as the "PORON" S2000 silicone by RogersCorporation of Woodstock, Conn. The "PORON" S2000 silicon is a closedcell foam that is nonabsorbent to blood and other body fluids. The foamis cut and provided in two sections 44A, 44B, such as shown in FIG. 14.The vulcanized silicone elastomer core 42 is centrally attached to oneof the sections with use of an adhesive, such as the NuSil 1137 adhesivePreferably, at least 3 centimeters of cellular silicone foam areprovided at all points between the peripheral edge of the holding member40 and the core 42. The other section of the foam is then positioned bythe use of adhesive preferably along the full engaging surface 46,including the other side of the core, to provide a unitary one pieceholding member. The holding member should then be allowed to cure for 24hours, trimmed of excess adhesive and cleaned with isopropyl alcohol.

In the preferred embodiment, once the two sections of the foam 44A and44B are joined by the adhesive with the core therein, the holding member40 may then be completely dip coated, as described above, with anonabsorbent layer 52, as best shown in FIG. 14.

Preferably, the coating is Part No. 40,000 a medical grade dimethylsilicone elastomer by Applied Silicone Corporation of Ventura, Calif.While the holding member would be nonabsorbent without the coatingbecause of the use of a closed cell foam, the coating is preferred toinsure the nonabsorbency and to provide the preferred slippery surfaceof the holding member 40. While the front surface 68 and the rearsurface 70 of the foam cut from the sheet will have a smooth surface,the edge will have a rougher surface because of the foam cells. Uponcoating, the front surface 68 and the rear surface 70 will become moreslippery and the edge will still have a sufficiently rough surface toprovide good engagement with the abdominal cavity walls.

A preferred medium size holding member 40 would include a center heightfrom the top of the indentation 48 to the top of the holding member 40at 50 of approximately 10.0 centimeters. The overall length of theholding member 40 at the tangential intersection at 48 is approximately26.0 centimeters. The overall height of the holding member 40 isapproximately 16.0 centimeters with a thickness of approximately 2.7centimeters. This 16.0 centimeter overall height and 10.0 centimeteractual holding member height provides 6.0 centimeters between theindentation to the bottom of the holding member about the patient'saorta and vena cava.

While both of the alternative embodiments, holding member 10, as shownin FIGS. 4-8, and holding member 10', shown in FIGS. 9 and 10, have thesame general bean-shaped configuration of the preferred holding member40, the holding members 10 and 40 have squared off peripheral edges 30and 49, respectively, and the holding member 10' has a radiused orcurved peripheral edge 32. However, it is to be understood that theholding members 10 and 40 could be fabricated with a radiused, curved,combination radiused and flat peripheral edge or other geometriccombination edge.

PROCEDURE FOR USE

Turning now to FIGS. 1-3 and 11, the procedure for use of the holdingmember is shown. During open pelvic surgery, a number of differentpresized holding members in individual sterile packages will preferablybe available to the surgeon. For example, aged patients and smallerpatients would use a different sized holding member than that describedabove for a medium sized patient. However, the overall configurations ofthese different size holding members can be predetermined by averaging anumber of Computerized Axial Tomography (CAT) scan cross sections on theabdominal cavity.

As best shown in FIGS. 2 and 3, an incision is used to open the pelvicarea of the patient P. A lower midline incision, lower transverseincision or any other medically acceptable opening may be used. Afterretracting the lateral abdominal walls W₃ and W₄ with blades R₂ and R₃,respectively, using a conventional 4-way retractor, such as the"BOOKWALTER" retractor R, as shown in FIGS. 1-3 and 11, the urinarybladder B is retracted with a suitably sized lower retractor blade R₁.The vertical distance between the sacral spine S and the umbilicus U oranterior wall W₁ adjacent the umbilicus U is then measured. Thismeasurement is used to select the proper size holding member.

Prior to insertion of the holding member, the patient P is placedmomentarily into an extreme "Trendelenburg" position allowing theintestines I and omentum O along with the colon J to recede into theupper abdomen as much as possible. FIG. 1 illustrates the basic"Trendelenburg" position, though the angle ⊖ could be larger as desiredby the surgeon. The holding member is then moved through the incisioninto the abdominal cavity C. If desired, using the concave portion ofthe holding members 10, 10' as a scoop or the front surface 68 of theholding member 40, the intestines I are moved further upwards in theupper abdomen until the member is positioned at or preferably 2centimeters below the umbilicus U. The rear surface of the holdingmembers 10 and 10', as best shown in FIG. 2, are concave to centrallylocate the intestines. As best shown in FIG. 11, the front surface ofthe holding member could include a plurality of holes to allow air tovent to and from the holding member, if desired. Even though the holdingmember is vented, it would still be nonabsorbent if a nonabsorbentmaterial is used for the holding member, such as a closed cell foam.

The holding members 10 and 40 will preferably have a cross section of anadditional 2 centimeters of foam in all directions than the actualaverage relaxed abdominal cavity measurements, except, of course, at therespective indentations 14, 48. This additional material will allow forcompression and variations of cavity contours and sizes.

The anterior and lateral abdominal walls of an average patient canwithstand considerable pressure from the inside or tension loadingduring surgery. However, as best shown in FIG. 11, the patient's aorta Aand vena cava V above the spine S in the center of the posterior wall W₂should be protected from more than about 15 millimeters mercurypressure. Since the cores 16, 42 of the respective holding members 10,40 are constructed of a more rigid elastomer, such as the vulcanizedsilicone elastomer described above, the holding member will transmitpressure to all the abdominal walls W. This core however should not comeinto contact with the aorta A and vena cava V. Of course, the density ofthe foam increases as the foam is compressed to the core. In the holdingmember 10 as the foam is compressed, a denser foam is adjacent theexposed core to protect the aorta A and vena cava V. In holding members10', 40, the more rigid core 26, 42 is embedded in a soft foam 28, 44A,44B to act as a buffer between the more rigid core 26, 42 and theresilient and compliant outer plastic tube 24 or the resilient andcompliant foam 44A, 44B.

After the holding member has been inserted, which should only take 1 or2 minutes, the patient P is repositioned to a more supine or horizontalposition to reduce pressure on the patient's diaphragm. As a precaution,it is recommended that the patient's pulse be checked in the commoniliac arteries after insertion of the holding member and one fingerinserted between the patient's aorta and vena cava and the holdingmember to be sure that pressure on the vena cava is not enough toobstruct flow. As a backup, if there is a reduction in venus return, theanesthetist would observe significant tachycardia.

In the alternative, the holding members as shown in the FIGS. can besized so that minimal or no pressure is exerted on the abdominal wallswith the holding member acting merely as a blocking member used incombination with the abdominal cavity walls to keep the intestines outof the operative field.

The fourth or upper blade R₄ of the retractor R is then moved into theincision and positioned adjacent the core of the respective holdingmember to hold the intestines I and omentum O in the upper abdomen clearof the operative field on the uterus T and/or ovary Q.

After completing the intra-abdominal phase of the surgery, the holdingmember is removed along with the 4-way retractor and the incision isclosed in the usual manner.

The foregoing disclosure and description of the invention areillustrative and explanatory thereof, and various changes in the size,shape and materials, as well in the details of the illustratedconstruction may be made without departing from the spirit of theinvention.

I claim:
 1. Apparatus adapted for use within an abdominal cavity of apatient, said cavity defined by an anterior wall, a posterior wall andlateral walls, said apparatus comprising:a U-shaped holding memberadapted to be received in the patient's abdominal cavity and having anedge formed of a resiliently deformable polymer and a core formed from apolymer that is more rigid than said resiliently deformable polymer, aresilient deformation of at least a portion of said edge of said holdingmember resulting in a residual reactive force against the abdominalcavity, said residual reactive force thereby assisting in positioningsaid holding member in the abdominal cavity; at least one bore in saidholding member wherein said at least one bore has a predeterminedlength; and said core including a first plate and a second plate, saidplates having an assembled length less than said predetermined length.2. Apparatus of claim 1 wherein said edge is fabricated from foam. 3.Apparatus of claim 1 where said edge of said holding member is sized toextend beyond the cross-section of the patient's relaxed abdominalcavity to enhance said residual reactive force.
 4. Apparatus of claim 1wherein the holding member is coated by a layer of polymer.
 5. Apparatusof claim 1 wherein said edge of the holding member is flat.
 6. Apparatusof claim 1 wherein said holding member having a presized indentation. 7.Apparatus of claim 6 wherein said indentation is adapted to bepositioned about the patient's aorta and vena cava.
 8. Apparatus adaptedfor use within an abdominal cavity of a patient, said cavity defined byan anterior wall, a posterior wall and lateral walls, said apparatuscomprising:a U-shaped holding member adapted to be received in thepatient's abdominal cavity and having an edge formed of a resilientlydeformable polymer and a core formed from a polymer that is more rigidthan said resiliently deformable polymer; at least one bore in saidholding member wherein said at least one bore has a predeterminedlength; and said core including a first plate and a second plate, saidplates having an assembled length less than said predetermined length.9. Apparatus of claim 8 wherein said edge is fabricated from foam. 10.Apparatus of claim 8 where said edge of said holding member is sized toextend beyond the cross-section of the patient's relaxed abdominalcavity.
 11. Apparatus of claim 8 wherein the holding member is coated bya layer of polymer.
 12. Apparatus of claim 8 wherein said edge of theholding member is flat.
 13. Apparatus of claim 8 wherein said holdingmember having a presized indentation.
 14. Apparatus of claim 13 whereinsaid indentation is adapted to be positioned about the patient's aortaand vena cava.
 15. Apparatus adapted for use within an abdominal cavityof a patient, said cavity defined by an anterior wall, a posterior walland lateral walls, said apparatus comprising:a U-shaped holding memberadapted to be received in the patient's abdominal cavity and having anedge formed of a resiliently deformable polymer and a core formed from apolymer that is more rigid than said resiliently deformable polymer; atleast one bore in said holding member not in communication with saidedge, wherein said at least one bore has a predetermined length. 16.Apparatus of claim 15 wherein said edge is fabricated from foam. 17.Apparatus of claim 15 where said edge of said holding member is sized toextend beyond the cross-section of the patient's relaxed abdominalcavity.
 18. Apparatus of claim 15 wherein the holding member is coatedby a layer of polymer.
 19. Apparatus of claim 15 wherein said edge ofthe holding member is flat.
 20. Apparatus of claim 15 wherein saidholding member having a presized indentation.